In recent years, a disparity has arisen with regard to increases in investment in digital equipment and increases in performance resulting from that investment. For that reason, analog computers are drawing more attention. On the other hand, it would be advantageous to develop a circuit with coexistence and cooperation of analog and digital circuits because there are many applications accumulated in the digital electronics field which it would support.
The inventors of the present invention have filed a patent application concerning a multiplication circuit for directly multiplying analog data and digital data. In such a multiplication circuit, it is usually difficult to sample and hold analog or multi-valued data without causing an error during transfer of data. Therefore, the above multiplication circuit has a problem concerning transfer errors.